MONTPELIER — The Shumlin administration and top legislative leaders will delegate to a nine-person panel the task of coming up with a way to finance single-payer health care.

The issue of financing has followed Gov. Peter Shumlin since he made single-payer the cornerstone of his gubernatorial agenda in 2010. The single-payer law enacted five months after his election directed his administration to deliver a financing plan by last month.

Shumlin, however, said it was still premature to tell Vermonters what tax he’d use to pay for the universal system.

Republican lawmakers late last month criticized the second-term Democrat for disregarding the statutory mandate, and asked him to identify his preferred tax forthwith. The decision to form the new panel, however, defers until 2015 the unveiling of an official financing recommendation.

The panel will include two appointees each from Shumlin, House Speaker Shap Smith and Senate President John Campbell. The three men will then decide together who should fill the three remaining seats.

“They will really dig into the issue of what the cost of the system will be and how the system is currently financed, and what a system going forward would be like if you financed it a different way,” Smith said. “I would see them putting forward a financing plan that supported a single-payer plan, or as close to single-payer as we could get under law.”

Administration Secretary Jeb Spaulding said the “commission” is still a work in progress, and that it’s unclear what kind of budget the group will have to work with. An internal memorandum circulated this week contemplated a $50,000 appropriation, but he said no decisions have been finalized.

Spaulding said a shifting federal landscape rendered obsolete the original delivery date for the single-payer financing plan. Shumlin had originally wanted to institute the new health care plan in 2014. An inability to secure the necessary federal waivers has delayed the start date until 2017. Spaulding said that gives lawmakers and the administration more time to craft a proposal.

“It’s become clear we don’t need to ask legislators to approve a plan until 2015, and that affords us the opportunity to have a thoughtful process to devise a financing plan,” he said.

While Spaulding doesn’t anticipate getting a final recommendation from the commission until early 2015, he said Vermonters should have some inkling of what’s coming by summer 2014.

“By that time I would imagine there would be possible funding features that will be discussed in public meetings,” Spaulding said. “There will be time for people to have public input, to make suggestions, before we see the final product.”